Of highland pabk



UNITED, STATES PATENT OFFICE.

THEODORE ALBRECHT, 0F ROYAL OAK, ROBERT PERETTO, Ol FARMINGTON, AND JOHN F. WANDERSEE, OF HIGHLAND PARK, MICHIGAN, ASSIGNORS TO FORD MOTOR COMPANY OF DELAWARE, OF HIGHLAND PARK, MlclHIGAN A CORPORA- TION OF DELAWARE.

METAL ALLOY.

Specification of Letters Patent. I Patented Apr. '26, 1921.

No Drawing. Original application filed September 10, 1919, .Seria1 No. 322,865.. Divided ancl this applie I cation filed. June 7, 1920. Serial No. 386,971.

322,865, of which this is a divisional application, and which is particularly applicable for use in the production or manufacture ofcutting or forming implements or tools requiring any or all of the qualities of toughness, hardness and ductility, and being espe cially capable of'withstanding the requirements necessary in cutting tools or instruments used on lathes, or milling cutters,

which are operated at great speed, or in forming implements which are under great pressure. 0

one object of, our invention is to produce an alloy which is of such hardness as to be capable of cutting or forming hard substances, and especially of cutting such hard substances while being operated at great speed, but which at the same time has the qualities of toughness, and ductility which will resist breakage and will not easily wear when in use for such purpose of cutting hard substances, and especially when being. operated at a high speed, and will also resist breakage when under great pressure.

A further object of our invention is to provide a metal alloy which can be graduated in toughness to make it best suited for the work which it is to perform. In this-connection it maybe mentioned that our alloy is especially adapted for cuttingtools which are subjected tov sudden impacts which tend to shatterthem if brittle, to heat from fricso that both on account of the original forming of the tool and the reshapinga'fter it has been used, it is desirable that the-material be ductile so that it may be workedinto uated so that the material will behard enough to secure a maximum amount of work therefrom and yet may be made as duetile as is consistent with the necessary hardness. We accomplish this. graduating of the relative hardness and ductility of-the material by'changing the proportion of iron therein. a

Our alloy makes an excellentlathe tool. For cutting 1.10 carbon steel on alhand fed lathe, we believe 7 88 revolutions per minute, or a little more, to be the most efficient speed, although it is possible to reach a maximum speed of more than twice that number. A cutting tool of our alloy will withstand this use longer than any other alloy we have'used,

and,.we believe, longer than any cutting tool used commercially.

Also a cutting tool made from our alloy will take a high luster and does'not corrode when exposed to the air or elements; the,

fumes of a chemical laboratory do not affeet it.

We are aware that-other alloys and high speed tools of various compositions have been used for these purposes, but the woalv ness of these metals lies in the fact that they are either so hard as tobe brittle, and easily broken when placed in use as ahighspeed cutting tool; too soft to withstand great pressure and wear required of them in such use; or arenot ductile.

A metal such as ours is hard enough to cut glass or steel; toughv enough to withstand a blow from a hammer, and ductile enough to bend slightly from the same blow of the.

hammer.

For melting, graphite crucibles may be used for the reason that it will absorb a prefer carbon, chromium, tungsten and 00- halt. The presence of iron in an amount graduated up to fifteen per cent, together with these constituents, will also make an excellent alloy for the production of such tools as herein specified.

It is not a requirement of our alloy that all of these metals be entirel or even substantially pure. It is possible to use ferrochromium which will contain about seventy to eighty'per cent. chromium and the other per cent. pure,-andcobalt ninety-seven per cent. ure.

7 It IS understood that in the use of. such metals not entirely pure, small percentages of other metals will appear in the alloy. This will be noted in the analysis hereinafter quoted in which these small quantities of other metals will appear, while only the metals carbon, chromium, cobalt, and tungsten were used, the small percentage of other metal being in and coming from such original constituents of the alloy.

We wish it to be understood, however, that pure, or substantially pure carbon, chromium, cobalt and tungsten, with the addition of iron, from two to fifteen per cent. iron, ifdesired, may be used with practically as good effect as those containing a small amount of other metals or impurities.

A chemical analysis of two of our experiments which produced an alloy of the properties contained in our invention showed the following constituents in their relative proportions:

Carbon 2. 54% Chromium 29.31 Tungsten 10.98 Iron 3'. 38 Silicone -1 1.34 Cobalt ...V- 504 Nickel. .16

' No. 2. a

Carbon 2.04% Chromium.- 26.06 Tungsten 11.86 Iron..-- 11,64

Silicon .22 a Cobalt 47. 31

Aluminum Trace.

Both of these alloys are within our invention and make exce nt alloys for cutting, milling and forming implements and tools such as hereinbefore described.

It is to be understood that these proportions may be varied to meet special re- 'member 0 quirements, as by varying the iron constituent for securing greater or less ductility.

We wish it to'be; understood that other metals of the chromium group .may be used in the place of tungsten in the compounding of our alloy. By other members of the chromium group, we mean either molybdenum or uranium. Y p

We claim as our invention:

1. Metal alloy composed of chromium from twenty to thirty-five per cent, tungsten from five to twenty per cent, iron from one to fifteen per cent, cobalt, andcarbon.

2. Metal alloy com osed of carbon two to five per cent, coba t thirt '-five to sixtyfive per cent, iron one to H ,ee'n per cent, chromium and tungsten. V

3. Metal alloy composed of chromium fifteen to forty per cent, cobalt thirty-five, to sixty-five per cent, iron one to fifteen per cent, tun ten and carborn I 4. Meta alloy composed of chromium from twenty to thirty-five per cent, tun ten from five to twenty per cent, cobalt orty to sixty per cent., carbon from two .to five per cent, and iron from one to fifteenper cent. 7

5. Metal allo composed of chromium from twenty to t irty-five per cent, tungsten from five to twenty per cent, cobaltforty to sixty percent, iron from one to fifteen per cent, and carbon more than one per cent,

6. Metal allo composed of chromium from twenty to t irty-five per' cent, tun ten from five to twenty'per cent.,cobalt orty to sixty per cent, carbon from two to five per cent, and iron less than fifteen per cent.

7. Metal alloy com osed of chromium from twent to thirtyve per cent; another f the chromium' group five to twenty per cent, iron from trace to fifteen per cent., cobalt and carbonxsaid allo being 29.31% chromium, 10.98%.tun stcn, 3.38%

iron, 1.34% nickel.

.7 10. Metal. alloy composed of 254% carsilicon, 50 .67% eebailt, and 16 3.38% iroi1,50.67% cobalt. I

11. Metal alloy cQmPosedj gfQfijt'i. carbon, 29.31% chromium,f'10.98% tungsten,

bon, 26.06% chromium, '11,% tungsten,

11.64% iron, 47.31% cobalt. 4

THEODORE, ALBRECHT.

ROBERT rnnn'rro'i JOHN F. WANDERSEE. 

